Generated by XState Viz: https://xstate.js.org/viz

machine.js

  const trafficLightMachine = Machine({
    initial: 'green',
    states: {
      green: {
        on: {
          TICK_EVENT: 'yellow'
        } 
      },
      yellow: {
        on: {
          TICK_EVENT: 'red',
        }
      },
      red: {
        on: {
          TICK_EVENT: 'green'
        }
      }
    }
  });